1. Field of the Invention
The present invention relates to a liquid crystal display field, and more particularly to a display device, a COA substrate and a manufacturing method for the same.
2. Description of Related Art
The technology adopted by a COA (Color Filter on Array) substrate is to integrate a color filter into an array substrate. Comparing with conventional alignment technology of a CF (color filter) substrate and a TFT (thin-film transistor), the COA technology provides a design strategy for decreasing a difficulty of alignment process of a manufacturing process for a display panel. Specifically, in the conventional technology, in order to eliminate an alignment error as much as possible, a wider black matrix (BM) is adopted to shield a light. However, in a COA substrate, the black matrix can be designed as a narrow trace width so that aperture ratio is increased. In addition, the COA substrate increases a distance between a pixel electrode and a metal trace through a photoresist layer so as to reduce a capacitive coupling effect of the pixel electrode and the metal trace so that a signal delay effect on the metal line can be improved to improve the panel quality.
However, when the COA substrate increases the distance between the metal trace and the pixel electrode, a connection difficulty between the pixel electrode and the metal trace is also increase. Specifically, between the pixel electrode and the metal trace, two insulation layers and a color filter are existed, a very deep through hole is required. In order prevent breaking of the trace of the pixel electrode or a poor contact among metal traces, an opening area of the through hole is larger. In a subsequent process, when liquid crystals drop, the liquid crystals are easily to gather at the location of the trough hole so that the deflection of the liquid crystals near the through hole is not controlled by a voltage, which causes an abnormal display and affects the quality of the panel of the display device.
In summary, it is necessary to provide a display device, a COA substrate and a manufacturing method for the same to solve the above problems.